"Here we are! Hooray!" Those were modest words for a momentous achievement. They came in a radio message from a six-man team of adventurers and scientists that reached the South Pole last week after a 3,213-km (1,992-mile) trek across Antarctica by dogsled. The expedition was the first to reach the pole by dogsled since Roald Amundsen beat Robert Scott there 78 years ago. But impressive as the feat is, it marks only the midpoint of an even more ambitious journey: a 6,450-km (4,000-mile) campaign that would be the first dogsled trip across the entire frozen continent.
The seven-month, $11 million Trans-Antarctica...